add Result as Void return type, add screen design file
commit from jim at 2013/8/10 12:00 from local machine
add some models

Not finish yet
use appengine api 1.7 instead of 1.8 due to some maven problems
implements All table entity according to yan's table design
implements all table entitys according to yan's table design.
prev commit is without new items.
Revert "use appengine api 1.7 instead of 1.8 due to some maven problems"

This reverts commit 15e6c6e7da3897c154251b03baf9545544f4b5e7.
small modifications on models and revert pom.xml to previous version
add design images
Update web_api.md
Update web_api.md
Small changes on models and DAOs
Implement MenuDAO and some services related to Menu
Finish the public access API